“Gimme Five” reloaded – A compact 5 band QRP SSB transceiver in SMD technology – TRANSMITTER spectrum analysis

Abstract

The 10 watts peak envelope power linear transmitter for single sideband operation will be examined.

Test conditions are: 10 watt pep on every band, rf line terminated with 50 ohm dummy load, input audio two-tone signal identically applied for each measurement.

Measurements have been taken with RIGOL DSA815 spectrum analyzer, RIGOL DS1054 digital oscilloscope and Goldstar DS7040 analog oscilloscope.

Measurements (Graphical presentation)

For the 5 radio frequency bands the spectral analysis show the following results:

DK7IH 5 band QRP SSB transceiver 2020 - Spectral analysis of output signal (audio two-tone modulated) 80m
DK7IH 5 band QRP SSB transceiver 2020 – Spectral analysis of output signal (audio two-tone modulated) 80m
DK7IH 5 band QRP SSB transceiver 2020 - Spectral analysis of output signal (audio two-tone modulated) 40m
DK7IH 5 band QRP SSB transceiver 2020 – Spectral analysis of output signal (audio two-tone modulated) 40m
DK7IH 5 band QRP SSB transceiver 2020 - Spectral analysis of output signal (audio two-tone modulated) 20m
DK7IH 5 band QRP SSB transceiver 2020 – Spectral analysis of output signal (audio two-tone modulated) 20m
DK7IH 5 band QRP SSB transceiver 2020 - Spectral analysis of output signal (audio two-tone modulated) 17m
DK7IH 5 band QRP SSB transceiver 2020 – Spectral analysis of output signal (audio two-tone modulated) 17m
DK7IH 5 band QRP SSB transceiver 2020 - Spectral analysis of output signal (audio two-tone modulated)
DK7IH 5 band QRP SSB transceiver 2020 – Spectral analysis of output signal (audio two-tone modulated)

Results

IMD3 on the 80, 40, 20 and 17 meter bands are quite acceptable, for 15 meters there is still some room for improvement. ;-))

Voltage examination

Even it is not spectrum analysis a voltage graph should also be discussed. The signal is shown for 14.200 MHz modulated with a dual-tone signal. Horizontal division is 10 volts per grid line:

DK7IH 5 band QRP SSB transceiver 2020 - Dual tone modulation on 14 2 MHz - Vertical division is 10 volts
DK7IH 5 band QRP SSB transceiver 2020 – Dual tone modulation on 14 2 MHz – Vertical division is 10 volts

vy 73 de Peter

Author: Peter (DK7IH)

Radioamateur since 1987, constructor of radio hardware, software developer, science teacher in secondary education.

2 thoughts on ““Gimme Five” reloaded – A compact 5 band QRP SSB transceiver in SMD technology – TRANSMITTER spectrum analysis”

  1. I signed up to receive emails about your radio designs, I did not sign up for more political ads; I get enough of those already, thank you.

    1. E-Mails about new entries on this blog are generated automatically by WordPress and I can’t remember having sent any political ads. But if there is any bothering, you’re free to unsubscribe. 73 de Peter

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